Learn about Character Classes in python regular expressions.
“Anyone who says he can see through women is missing a lot.” ― Groucho Marx
New to regular expressions? Start here.
In the last article, we covered some beginning aspects of regular expressions in python. We now continue to examine details of character classes.
Continue reading “Python Regular Expressions Tutorial – Part 2”
A Gentle Introduction to Python Regular Expressions
“Suspect each moment, for it is a thief, tiptoeing away with more than it brings.” ― John Updike, A Month Of Sundays
Continue reading “Python Regular Expressions Tutorial – Part 1”
Basics of building a blockchain using python, part 1
“Even if you are on the right track, you’ll get run over if you just sit there.” ― Will Rogers
A Blockchain is all the craze right now. With the Bitcoin price on a runaway track, everyone wants in on the bitcoin bandwagon. While buying and selling bitcoin and other cryptocurrencies is good (or bad, depending on your finances!), let us learn the basics of the technology behind these cryptocurrencies. In the process we will also attempt to come up with the building blocks of the technology starting from scratch.
Continue reading “Python Crypto Basics for Building a Blockchain”
Collection of Checks for Readable and Writable Files.
“Education is the most powerful weapon which you can use to change the world.” ― Nelson Mandela
It can be a bit cumbersome at times to check for read or write permission on a file. The check might succeed but the actual operation could fail. Also, quite a few edge cases need to be covered to get a reasonable answer from such a check. In this article, we cover some issues with regards to checking read and write permission on a file.
Continue reading “Python How to Check if File can be Read or Written”
Easily incorporate strong AES encryption into your programs.
“Believe in your infinite potential. Your only limitations are those you set upon yourself.” ― Roy T. Bennett, The Light in the Heart
Pycrypto is a python module that provides cryptographic services. Pycrypto is somewhat similar to JCE (Java Cryptography Extension) for Java. In our experience JCE is more extensive and complete, and the documentation for JCE is also more complete. That being said, pycrypto is a pretty good module covering many aspects of cryptography.
Continue reading “Using AES for Encryption and Decryption in Python Pycrypto”
Make your life easier with these itertools when dealing with iterables
“A lie gets halfway around the world before the truth has a chance to get its pants on.” ― Anonymous
Python provides the itertools package which provides convenience functions for many common iterator operations. We have covered count(), cycle() and chain() in the first part of this series, and compress(), dropwhile(), and groupby() in the second part. In this article, we present a few examples of ifilter(), islice(), imap() and izip().
Continue reading “Python itertools – ifilter, islice, imap, izip”
More on downloading HTTP URLs using urllib2.
“I like the night. Without the dark, we’d never see the stars.” ― Stephenie Meyer, Twilight
Python provides the well-regarded urllib2 module for opening URLs. Let us investigate some of the capabilities of this module, shall we? Note that most use cases are better served by using the higher level Requests module. However, you should know about the available options.
Continue reading “Python HTTP Client using urllib2”
Learn about all the facilities available with python string formatting
“The saddest aspect of life right now is that science gathers knowledge faster than society gathers wisdom.” ― Isaac Asimov
String formatting in python is somewhat complicated by the fact that there are a lot of flags and options. Let us learn about them.
Continue reading “Python String Formatting Examples”
Remove items from a List and more.
“Happiness is a perfume you cannot pour on others without getting some on yourself.” ― Ralph Waldo Emerson
In a previous article, we covered some python list methods related to adding items. Let us now continue the review of more list methods.
Continue reading “Python – More List Methods and Recipes”
Check out this refresher on ways to add items to python lists
“Share your knowledge. It is a way to achieve immortality.” ― Dalai Lama XIV
Continue reading “Python List Methods: Adding Items”